The Air Care On-road testing system is being used only for study purposes now, but it doesn’t take much imagination to see where this could head. In addition to a radar gun the cops could be equipped with an “emissions gun,” and if you’re over the limit I could see this scenario playing out:

Driver: “What’s wrong officer, was I speeding?”

Police officer: “No but our Air Care gun clocked you at 3.5 grams pm per brake horsepower, and your NOx is through the roof!